When Should I Do a Valve Clearance Adjustment?

When is the right time to do a valve clearance adjustment on a motorcycle or ATV? Opinions differ on when this should be done, and our resident pro John Talley knows a little something about valve clearances.

John and special guest Garrett Sifford took part in another Friday edition of Partzilla Live Q&A, in which John addressed a difference of opinions on when exactly a valve clearance (or valve lash) adjustment should be done. Here's what John had to say about one of our viewers' questions regarding the right temperature for doing a valve adjustment.

Valve clearance adjustment

When Is a Valve Adjustment Needed?

I’ve heard different opinions about doing valve adjustments. Do you do it when the motor is hot, cold or warm and why?

John Talley: Well, you definitely want to do it when it’s cold because otherwise you’d be aiming for a temperature that’s going to be constantly changing. What I can tell you when they actually do the measurements that they base these on at the factory, I believe they have controlled addition of around 75 degrees, so if you really want to be deadly accurate, make sure your environment is around 75-80 degrees, but that’s the reason why. If you try to do it warm, by the time you started the procedure, especially on a sports bike, it’s going to be a different temperature by the time you get to that last set of valves. So that would be why, you basically want it to be room temperature, and that’ll get you as accurate as possible by doing it that way.